I sat down to my reloading bench this morning to put together some .45 Colt ammo for my new Ruger Flattop. It got me to thinking: The .45 Colt just might be the best—or at least the most versatile—handgun cartridge of all time. Of course, that only holds true if you consider the role of a handgun in its traditional sense—a reactive tool for stopping threatening or edible creatures at close range.